Electric heating unit



Patented May 17, 1921.

UNITED. STATES PATENT, OFFICE.

EKBGOTT, 01' EAST PITTSBURGH, PENNSYLVANIA, ASSIGNOR T0 TESTING- HOUSEILEUIBIC -& MANUFACTURING COMPANY, A CORPORATION OF PENNSYL- veins.

Application filed April 21,

My invention relates to electric heating devices and particularly toelectric heating units. I p

The object of my invention is to provide a relatively simple andlight-weight heating unit that shall permit of easy and quickassembly'and disassembly. y

In practicing my invention, I provide a plate of sheet metal, and formtherefrom a plurality of pairs of cooperating flanged portions that aresubstantially co-extensive and are bent to lie closely adjacent to eachother. They are provided with a plurality of spaced openin 's 1n. theedges thereof to receive perforated sulating material for sup orting aresistor member. Each flange portion has a plurality of integral lugs atthe edge thereof, the respective lugs being bent to substantiallyarcuate shape and alined to ermitof locating therein a rod that inter tstherewith to hold the flan (1 portions and the refractory thimbles in teir proper operative positions relatively to each other. I

In the single sheet of drawings,

Figure 1 is atop plan view of a heating unit embodying my invention,portions thereof being shown in section,

. Fig. 2 is a vitamin lateral section therethrough, taken on the lineIIII of Fig. 1, and

Fig. 3 is a view, in side elevation, of a portion of a heating unitembodying myinvention.

A heating unit 11 comprises a sheet 12 of any suitable metal that'may beof any suitable or desired contour and dimensions, but is. here shown asbeing substantially .rec tangular in shape. 1218 provided, at each sidethereof, with integral and bent-over flange portions 13 and 14 tostiffen the plate 12. i

A plurality of flange portions 15 and 16, 17 and 18, and 19 and 21 arepunched out of the plate 12 and bent in op osite' directions,substantially as illustrate in Fig.2 of the drawings.

As the co-operating pairs of flanged portions are similar, only one pairthereof will be described in detail. The flange portion 15 is unched outof the metal plate 12. The rig t hand portion thereof remaininginthimbles of refractory electric-in- 7 v nnnc'rmo HEATING UNIT.

1924. Serial No. 707,827.

portion remains integral with the plate 12 and, whenvfinally bent, thetwo flange portions have their outer portions located closely adjacentto each other and substantially coextensive. As illustrated moreparticularly in Fig. 2 of the drawings, the inner portions of therespective flanges are bent to arcuate shape in order that the stress inthe material may not become so great as to cause the flange portions tobe torn away from the plate 12.

Each flange portion is provided'with a plurality of spaced openings22 inthe out-- s de edge thereof, as is illustrated more particularly in Fig.3 of the drawings. A thimble 23, of refractory electric-insulatingmaterial, is located in each of the openings 22 and comprises aperforated member having an intermediate portion of reduced diameter inorder that it may fit into and interlock with theopening 22 in which itis located. I preferably employ a thimble that is made up of twoco-operating halves in order that a broken thimble may be easilv andquickly replaced. f u i The flange portion 15 is provided with aplurality of integral and spaced lugs 24 at its outer edge, that arebent to substantially arcuate form, as illustrated more particularly inthe left-hand side of Fig. 2 of the drawings. The flange portion 16 isprovided wlth a plurality of substantially similar lugs 25, that arebent to substantially arcuate form, but in the oppositedirection to'thatin which the lugs 24 are bent.

The set of lugs 24 and 25 are in alinement with each other, and a metalrod 26 extends therethrough and is substantially co-extensive with theflange portions 15 and 16. The metal rod 26 serves not only to hold theouter edges of the flange portions 15 and 16 in their proper operativepositions relatively to each other, but serves also to hold the thimbles23 in their proper operative positions in the openings 22 in therespective co-operating flanges. A resistor member 27 that comprises ahelically wound resistor wire extends through the perforated thimbles 23and therebetween in any suitable or desired con.

figuration, relatively to the surface of the plate 12. lVhile I haveshown the openings 22 as alined laterally of the plate 12, this is notnecessary, as any suitable or desired location of the openings in therespective pairs of flange portions may be employed.

In case one of the thimbles 23 should become defective, it is onlynecessary to pull out the rod 26 associated therewith to a sufficientdistance to permit of removing the damaged tliimble and of replacing itby a new thimble, an operation that is easily and quickly effectedwhere, as hereinbefore stated, a split thimble is employed. After thereplacement of the thimble, the rod 26 may be moved back to its properoperative position as hereinbefore described.

Various modifications and changes may be made Without departing from thespirit and scope of the invention, and I desire therefore that only suchlimitations shall be placed thereon as are imposed by the prior art.

I claim as my invention:

1. In an. electric heating unit, in combination, a metal member having apair of integral laterally extending portions each having an openingtherein ad acent to one edge thereof, each portion having an integrallug at said edge, the two lugs being bent to oppositely curved shape, athimble of refractory material in said. openings, and a rodinter-fitting with said curved lugs to main-' tain them and the thimblein proper operative positions.

2. In an electric heating unit, in combina tion, a pair of metal membershaving an opening therein adjacent to an edge thereof said metal membershavin oppositely extending curved lugs at saic edge, a refractorythimble in said opening, and a rod extending through said curved lugsfor hold ing the outer edges of said metal members in proper operativepositions relatively to each other.

3. In an electric heating unit, in combination, a pair of metal membershaving an opening therein adjacent to an edge thereof, said metalmembers having oppositely extending curved lugs at said edge, a refraotory thiinble in said opening, and a rod extending through said curvedlugs for holding the outer edges of said metal members in properoperative positions relatively to each other and for holding saidlhimblc in said and each flange portion having an integral andoppositely-extending arcuate lug at the edge thereof, a perforatedrefractory thimble in said opening, means in said arcuatc lugs forholding said flange portions together and for holding said thimble insaid opening, and a resistor member extending through said thimble.

5. In an electric heating unit, in combination, a pair of co-operatingflange portions having a plurality of spaced openings in their outeredges, spaced pairs of integral and oppositely-bent arcuate lugs on saidflange port-ions, refractory thimbles in said openings, and a rodextending through said arcuate lugs for holding said flange portions andfor holding said refractory thimbles in said openings.

6. In an electric heating unit, in combination, a pair of co-operatingflange portions, each flange having a plurality ot spaced openings and aplurality of spaced integral lugs at the edge thereof bent tosubstantially arcuate form and in substantial alinemcnt with each other,perforated refractory thimbles in said openings, a rod extending throughsaid alined lugs to hold said flange portions and said thimbles in saidopenings,

and a resistor member extending throughsaid erforated thimbles.

- 7. ii an electric heating unit, in combination, a metal member havinga plurality of pairs of integral laterally extending portions, eachhaving an opening therein adjacent to one edge thereof, each portionhaving an integral lug at said edge, the two lugs being bent tooppositely curved shape, a thimble of refractory material in saidopenings, and a rod extending through said curved lugs for holding theother edges of said metal members in proper operative positionsrelatively to each other.

In testimony whereof, I have hereunto subscribed my name this l6th dayof April, 1924.

KARL EHRGOT'I.

